The present invention relates to an extrusion blow molding machine used for manufacturing many different products in the polymer industry, and particularly to an electrically-driven extrusion blow molding machine and an extrusion blow molding method realized using the machine.
Blow molding is one of the three major molding technologies used for the polymeric materials. Extrusion blow molding accounts for a large proportion in the blow molding area. The parison thickness programming and mold-clamping apparatuses are both hydraulically-driven in most of the available extrusion blow molding machines. The hydraulically-driven apparatus has some disadvantages, such as poorer control accuracy and repeatability, higher energy consumption and noise, unsuitable for “clean room” manufacturing environments, and so on. Therefore, for some applications, the hydraulically-driven apparatus is facing competition from the electrically-driven one. However, the available electrically-driven blow molding machines still have some disadvantages, such as a complicated structure and a high manufacturing cost. The parison thickness programming apparatus in the available electrically-driven blow molding machine is generally driven by a servo motor. The frequent start and stop and frequent normal and opposite running of the servo motors result in their heating and so shorten their service life. Moreover, the mold-opening/closing and mold-moving assemblies of the mold-clamping apparatus in the available electrically-driven blow molding machines are generally driven by a set of separate electric transmission device including a servo motor, respectively.